检索结果-南通市图书馆

A Review on Particle Reinforced Mg Matrix Composites Fabricated by Powder Metallurgy

在线全文

学校读者我要写书评

暂无评论

Acta Metallurgica Sinica(English Letters) 2024年第3期37卷 391-400页

作者： Zhiyuan Liu Li Jin Jian Zeng Fulin Wang Fenghua Wang Shuai Dong Jie Dong National Engineering research Center of light alloy Net Forming and State Key Laboratory of Metal Matrix Composite School of Materials Science and EngineeringShanghai Jiao Tong UniversityShanghai 200240China

This paper provides a comprehensive review of research progress in particle-reinforced Mg matrix composites prepared via powder metallurgy.The article discusses different strategies,such as micro-sized,nano-sized particles,and multi-particle hybridization,which has been employed to enhance the performance of the composites.In addition,a range of preparation techniques that optimize the dispersion of the reinforcing particles are summarized.The paper also highlights how the different configurations between the reinforcements and matrix alloy impact the composites’performance.Finally,the article outlines the prospects of particles reinforced Mg matrix composites fabricated via powder metallurgy and recommends modification methods that could be explored to further develop these materials for various applications.

关键词： Magnesium matrix composites Reinforcing particle Powder metallurgy Mechanical properties Configuration

Microstructure and impact behavior of Mg-4Al-5RE-xGd cast magnesium alloys

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Magnesium and alloys 2024年第5期12卷 1799-1814页

作者： Jie Wei Qudong Wang Huisheng Cai Mahmoud Ebrahimi Chuan Lei National Engineering research Center of light alloy Net Forming and Key State Laboratory of Metal Matrix Composites School of Materials Science and Engineering Shanghai Jiao Tong University

This work investigated the microstructure and impact behavior of Mg-4Al-5RE-xGd（RE represents La-Ce mischmetal; x = 0, 0.2,0.7 wt.%） alloys cast by high-pressure die casting（HPDC）, permanent mold casting（PMC）, and sand casting（SC） techniques. The results indicated that with increasing Gd content, the grain sizes of the HPDC alloy had a slight change, but the grains of the PMC and SC alloys were significantly refined. Besides, the acicular Al11RE3phase was modified into the short-rod shape under the three casting conditions. The impact toughness of the studied alloy was mainly dominated by the absorbed energy during the crack initiation. With increasing Gd content,the impact toughness of the studied alloy monotonically increased due to the lower tendency of the modified second phase toward crack initiation. The impact stress was higher than the tensile stress, exhibiting a strain rate sensitivity for the mechanical response; however, the HPDC alloy had an inconsistent strain rate sensitivity during the impact event due to the transformation of the deformation mechanism from twinning to slip with increasing strain. Abundant dimples covered the fracture surface of the fine-grained HPDC alloys, indicating a typical ductile fracture. Nevertheless, due to the deficient {■} twinning activity and the suppressed grain boundary sliding during the impact event, the HPDC alloys showed insufficient plastic deformation capacity.

关键词： Mg-Al-RE alloy Gadolinium Microstructure Impact behavior

Degradation and biocompatibility of one-step electrodeposited magnesium thioctic acid/magnesium hydroxide hybrid coatings on ZE21B alloys for cardiovascular stents

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Journal of Magnesium and alloys 2024年第1期12卷 120-138页

作者： Zhao-Qi Zhang Bing-Zhi Li Pei-Duo Tong Shao-Kang Guan Li Wang Zheng-Hui Qiu Cun-Guo Lin Rong-Chang Zeng School of Material Science and Engineering&Henan Key Laboratory of Advanced Magnesium alloy&Key Laboratory of Materials Processing and Mold Technology(Ministry of Education) Zhengzhou University100 Science RoadZhengzhou 450001China State Key Laboratory for Marine Corrosion and Protection Luoyang Ship Material Research InstituteQingdao 266101China Corrosion Laboratory for light Metals College of Material Science and EngineeringShandong University of Science and TechnologyQingdao 266590China

Constructing a functional hybrid coating appears to be a promising strategy for addressing the poor corrosion resistance and insufficient endothelialization of Mg-based stents.Nevertheless,the steps for preparing composite coatings are usually complicated and time-consuming.Herein,a novel composite coating,composed of bioactive magnesium thioctic acid(MTA)layer formed by deposition and corrosion-resistant magnesium hydroxide(Mg(OH)_(2))layer grown in situ,is simply fabricated on ZE21B alloys via one-step electrodeposition.Scanning electron microscopy(SEM)shows that the electrodeposited coating has a compact and uniform structure.And the high adhesion of the MTA/Mg(OH)_(2)hybrid coating is also confirmed by the micro-scratch test.Electrochemical test,scanning kelvin probe(SKP),and hydrogen evolution measurement indicate that the hybrid coating effectively reduces the degradation rate of Mg substrates.Haemocompatibility experiment and cell culture trial detect that the composite coating is of fine biocompatibility.Finally,the preparation mechanism of MTA/Mg(OH)_(2)hybrid coatings is discussed and proposed.This coating shows a great potential application for cardiovascular stents.

关键词： Magnesium alloy Corrosion resistance Hybrid coating Endothelialization Biocompatibility

Activation of dislocations in Mg with solute Y

在线全文

学校读者我要写书评

暂无评论

Journal of Magnesium and alloys 2024年第3期12卷 1045-1053页

作者： Alireza Maldar Leyun Wang Boyu Liu Wenjun Liu Zhaohui Jin Bijin Zhou Xiaoqin Zeng National Engineering research Center of light alloy Net Forming Shanghai Jiao Tong UniversityShanghai 200240China State Key Laboratory for Mechanical Behavior of Materials Xi’an Jiaotong UniversityXi’an 710049China Advanced Photon Source Argonne National LaboratoryIL 60439USA Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of Sciences72 Wenhua RoadShenyang 110016China School of Mechanical Engineering Suzhou University of Science and TechnologySuzhou 215009China

Mg-Y cast alloy shows excellent ductility(elongation to failure>15%)compared with pure Mg and commercial Mg cast alloys.By monitoring the microstructure evolution during an in situ tensile test of a Mg-2.5 wt%Y alloy,we identify the activation of prismaticslip,which is rare in Mg.Synchrotron X-ray micro-beam Laue diffraction(μ-Laue)and transmission electron microscopy revealed the morphology of prismaticslip bands and individualdislocations.Density functional theory and molecular dynamics calculations indicate that solute Y can significantly reduce the stacking fault energy(SFE)alongdirection on prismatic plane in Mg lattice and thus facilitate the nucleation ofdislocations during deformation.The presence of freedislocations in the Mg lattice can also lead to nucleation of{10–12}twins even under unfavorable geometric conditions.

关键词： alloy microstructure ductility

Interaction between Surface Acoustic Wave and Quantum Hall Effects

在线全文

学校读者我要写书评

暂无评论

Chinese Physics Letters 2024年第4期41卷 105-109页

作者：刘萧吴蒙蒙王任飞王兴豪张文锋董昱江杜瑞瑞刘阳林熙 International Center for Quantum Materials Peking UniversityBeijing 100871China Center for Excellence University of Chinese Academy of SciencesBeijing 100190China Hefei National Laboratory Hefei 230088China Interdisciplinary institute of light-Element Quantum Materials and research Center for light-Element Advanced Materials Peking UniversityBeijing 100871China

Surface acoustic wave(SAW)is a powerful technique for investigating quantum phases appearing in twodimensional electron systems.The electrons respond to the piezoelectric field of SAW through screening,attenuating its amplitude,and shifting its velocity,which is described by the relaxation model.In this work,we systematically study this interaction using orders of magnitude lower SAW amplitude than those in previous studies.At high magnetic fields,when electrons form highly correlated states such as the quantum Hall effect,we observe an anomalously large attenuation of SAW,while the acoustic speed remains considerably high,inconsistent with the conventional relaxation model.This anomaly exists only when the SAW power is sufficiently low.

关键词： relaxation quantum inconsistent

Layered kagome compound Na_(2)Ni_(3)S_(4)with topological flat band

在线全文

学校读者我要写书评

暂无评论

Chinese Physics B 2024年第5期33卷 153-159页

作者：叶君耀林益浩王浩哲宋志达冯济谢韦伟贾爽 International Center for Quantum Materials School of PhysicsPeking UniversityBeijing 100871China Department of Chemistry Michigan State UniversityMI48824USA Hefei National Laboratory Hefei 230088China Interdisciplinary institute of light-Element Quantum Materials and research Center for light-Element Advanced Materials Peking UniversityBeijing 100871China

We report structural and electronic properties of Na_(2)Ni_(3)S_(4),a quasi-two-dimensional compound composed of alternating layers of[Ni_(3)S_(4)]^(2-)and Na^(+).The compound features a remarkable Ni-based kagome lattice with a square planar configuration of four surrounding S atoms for each Ni atom.Magnetization and electrical measurements reveal a weak paramagnetic insulator with a gap of about 0.5 eV.Our band structure calculation highlights a set of topological flat bands of the kagome lattice derived from the rotated dxz-orbital with C_(3)+T symmetry in the presence of crystal-field splitting.

关键词： kagome lattice flat band

High formability Mg-Zn-Gd wire facilitates ACL reconstruction via its swift degradation to accelerate intra-tunnel endochondral ossification

在线全文

学校读者我要写书评

暂无评论

Journal of Magnesium and alloys 2024年第1期12卷 295-315页

作者： Xuan He Ye Li Hongwei Miao Jiankun Xu Michael Tim-yun Ong Chenmin Wang Lizhen Zheng Jiali Wang Le Huang Haiyue Zu Zhi Yao Jie Mi Bingyang Dai Xu Li Patrick Shu-hang Yung Guangyin Yuan Ling Qin Musculoskeletal research Laboratory of Department of Orthopaedics&Traumatology and Innovative Orthopaedic Biomaterial and Drug Translational research Laboratory of Li Ka Shing institute of Health Sciences The Chinese University of Hong KongHong KongChina National Engineering research Center of light alloy Net Forming School of Materials Science&EngineeringShanghai Jiao Tong UniversityShanghaiChina Department of Orthopaedics and Traumatology Li Ka Shing Faculty of MedicineThe University of Hong KongHong KongChina Orthopaedic Department Peking University Third HospitalBeijingChina Department of Rehabilitation Sciences The Hong Kong Polytechnic UniversityHong KongChina

After reconstructing the anterior cruciate ligament(ACL),unsatisfactory bone tendon interface healing may often induce tunnel enlargement at the early healing stage.With good biological features and high formability,Magnesium-Zinc-Gadolinium(ZG21)wires are developed to bunch the tendon graft for matching the bone tunnel during transplantation.Microstructure,tensile strength,degradation,and cytotoxicity of ZG21 wire are evaluated.The rabbit model is used for assessing the biological effects of ZG21 wire by Micro-CT,histology,and mechanical test.The SEM/EDS,immunochemistry,and in vitro assessments are performed to investigate the underlying mechanism.Material tests demonstrate the high formability of ZG21 wire as surgical suture.Micro-CT shows ZG21 wire degradation accelerates tunnel bone formation,and histologically with earlier and more fibrocartilage regeneration at the healing interface.The mechanical test shows higher ultimate load in the ZG21 group.The SEM/EDS presents ZG21 wire degradation triggered calcium phosphate(Ca-P)deposition.IHC results demonstrate upregulation of Wnt3a,BMP2,and VEGF at the early phase and TGFβ3 and Type II collagen at the late phase of healing.In vitro tests also confirmed the Ca-P in the metal extract could elevate the expression of Wnt3a,βcatenin,ocn and opn to stimulate osteogenesis.Ex vivo tests of clinical samples indicated suturing with ZG21 wire did not weaken the ultimate loading of human tendon tissue.In conclusion,the ZG21 wire is feasible for tendon graft bunching.Its degradation products accelerated intra-tunnel endochondral ossification at the early healing stage and therefore enhanced bone-tendon interface healing in ACL reconstruction.

关键词： Magnesium wire ACL reconstruction Magnesium alloy Biomaterials Endochondral ossification

不同应力水平对2195-T34 Al-Li合金时效行为的影响机制研究

在线全文

学校读者我要写书评

暂无评论

Journal of Central South University 2024年第1期31卷 11-24页

作者：陈非湛利华徐永谦刘春辉马博林曾泉清胡正根朱文俐鄢东洋 light alloy research institute of Central South University Changsha 410083China School of Mechanical and Electrical Engineering Central South UniversityChangsha 410083China State Key Laboratory of High-performance Complex Manufacturing Central South UniversityChangsha 410083China Beijing institute of Astronautical Systems Engineering Beijing 100176China

研究了不同应力水平下2195-T34 Al-Li合金的时效特性变化。当应力低于材料的高温屈服强度(YS)时,低应力时效(LSA)和无应力时效(SFA)试样的屈服强度和延伸率(EL)相近。当应力超过材料的高温屈服强度时,试样的极限拉伸强度(UTS)和伸长率... 详细信息

研究了不同应力水平下2195-T34 Al-Li合金的时效特性变化。当应力低于材料的高温屈服强度(YS)时,低应力时效(LSA)和无应力时效(SFA)试样的屈服强度和延伸率(EL)相近。当应力超过材料的高温屈服强度时,试样的极限拉伸强度(UTS)和伸长率显著下降,表明应力的增加降低了材料的抗破坏性。透射电子显微镜(TEM)和扫描电子显微镜(SEM)的观察结果表明:应力对材料时效性能的影响归因于内部析出物特征和晶界富铜析出物的共同作用。应力的增加促使铜原子在晶界发生偏析形成富铜析出物,同时促进了晶界无沉淀区(PFZ)的形成,而富铜析出物是脆性相,可作为损伤的起始位置,容易导致裂纹萌生和发展,降低材料的延展性。

关键词：铝锂合金应力水平时效力学性能

Rational design of AgGaS/ZnS/ZnS quantum dots with a near-unity photoluminescence quantum yield via double shelling scheme

在线全文

学校读者我要写书评

暂无评论

Journal of Materials Science & Technology 2024年第2期169卷 235-242页

作者： H.X.Lu H.Liu Z.Z.Fu Y.Y.Chen H.Q.Dai Z.Hu W.L.Zhang R.Q.Guo institute for Electric light Sources School of Information Science and TechnologyFudan UniversityShanghai 200433China institute of Future lighting Academy for Engineering and TechnologyFudan UniversityShanghai 200433China Yiwu research institute of Fudan University YiwuZhejiang 322000China Zhongshan-Fudan Joint Innovation Center Zhongshan 528437China

In this study,a two-step method was used to synthesize highly luminescent AgGaS/ZnS/ZnS quantum dots(QDs).In the first step,an inner ZnS shell was formed via a one-pot method,which resulted in a smaller lattice mismatch between the AgGaS core and the outer ZnS shell,thereby facilitating the formation of a thick outer shell.After the two-step shelling process,the synthesized AgGaS/ZnS/ZnS QDs showed an excellent photoluminescence quantum yield(PLQY)of 96.4%with a peak wavelength of 508 nm,repre-senting the highest PLQY reported thus far for AgGaS QDs.Furthermore,the effect of halogen ions in Zn precursors on the shelling process was investigated.It was proposed that the capacity of halogen ions to coordinate with the QDs influenced the balance between Zn cation diffusion and ZnS shelling reaction.Specifically,the ZnS shelling reaction was dominant when ZnCl_(2)was employed,while Zn cation diffusion was the dominant process under the I^(−)-rich environment.This work provides insights into the interfacial restructuring during the ZnS shelling and offers a clear map for the tailored synthesis of core/shell QDs.

关键词： AgGaS Quantum dots Photoluminescence Core/shell alloyed core/shell interface